The present invention relates to fuzing systems and more particularly to optical fuzing systems wherein the target is detected by a first detecting channel and if the target is detected by a second detecting channel within a predetermined time interval, a firing signal is generated. This system functions with a very high probability of target kills when the missile is overtaking the target from the rear hemisphere. When the missile is approaching the target from other than the rear, the missile may have passed the target before the second channel detector sees the target and the result is the warhead explodes too late to damage the target.